On Tue, Mar 13, 2012 at 1:26 PM, Markus Falb markus.falb@fasel.at wrote:
Tape, and tape drives, have a bad reputation. They are difficult and time consuming to verify.
Harddisks have a bad reputation too. They fail regulary.
Yes, but if they are online, in raid, with smart monitoring, you swap them (maybe every 5 years or so, getting better...) and let the replacement re-sync. Anything else and you don't find out that it is dead until you are doing a restore.
Anyway, I would not feel comfortable about backing up data residing on a harddisk to another harddisk. I believe that a backup media has to provide different characteristics than the original media. An incident that harms original should not harm the backup.
I thought the old saying was that if something was important you should have 3 copies, and don't let the person who destroyed the first 2 touch the 3rd.
What about if a firmware bug destroys all data on day XXX on all harddisks ? Well, extra paranoid maybe and of course I have not thought of all possible things that *could* happen.
If you've been replacing your raid drives as they die over the years, you probably won't be left with all the same model when this event happens.